Only Natural
by StillThunder86
Summary: Two fight with their fists. Two fight with their hearts. And Bishop holds all the cards. *Check out Outasync's continuation of this story! It's in my favorites!*


**Disclaimer:** TMNT and related characters still owned by Kevin Eastman and Peter Laird. Them greedy fellows...

* Plot bunnies attack even during last-minute shopping. Beware the girl standing in the Christmas aisle with glazed eyes! Rated T for the blood.

Only Natural

"Are we supposed ta be seein' somethin' here?"

The strap binding Donatello's head made it impossible to look towards his brother. The best he could manage was a blurred, dark green figure at the edge of his vision. Just enough to see his brother was in the same position as himself.

Upright on a steel table, head strapped as back as neck and shell would allow. Three thick bands running across the chest, stomach, and thighs. Wrists and ankles shackled tight by leather cuffs.

They faced a shaded window viewing a small, white room. In the thirty minutes in which they'd demanded to know if the other was hurt, then established that neither was _lying_ about not being hurt, and tested the strength of their tethers, it remained empty.

But it made him nervous. Gave him that tingly being-watched sensation at the back of his neck.

"Don?"

"I'm not sure," he said at last. "But this is a two-way mirror."

"Like in interrogation rooms?"

"Yes."

Raphael went silent for a moment and when he spoke again, Donnie was startled at the tightness in his voice. "Who'd we have ta watch bein'…"

"Two guesses, Raph."

Only two others worth the ambush Bishop had set for them.

His remaining brother growled and Donnie heard him thrash. He bit his lip to keep from scolding him. They had to conserve their energy for whatever was coming. But Raph gave up after a minute and he was thankful he'd kept his mouth shut. He wasn't in the mood to be accused of being a Leo-substitute just then.

After that, they sat in silence and waited for their host to show up.

Silent, but not idle. Donatello wriggled and pulled at his own straps, sure that if he could just get a look at them, he'd see a way out. His wrists had been fixed into braces, leaving his fingers free, but keeping his joints immobile. Between that and the ache in his strained neck, he felt the first tendrils of claustrophobia tightening around his chest

He took a few breaths and focused on the room in front of them. His brothers need him losing his head as much as they needed Raph exhausted. He had to calm down. He had to -

"Raph!"

"Wha'?" his brother snarled.

In the silent white, a tall panel had been withdrawn, creating a black void. A familiar, three-fingered hand curled out of the darkness and Leonardo slunk into sight.

"LEO!" Donnie flinched, his ears ringing. "Leo, we're here! Jes through da window! In here!"

Their brother turned in a slow circle, crouched low to brace himself on his fingertips. He had been stripped of his gear. When the panel slid back into place, he started, lunging for the corner and looking around with sharp, bird-like twitches.

"Leo!"

Don ground his teeth. "He can't hear you."

"No kiddin'," Raph growled. "Don't mean it can't make me feel betta…" His voice softened. "Why's he actin' like that?"

Leo rocked, gently, his arm wrapping around his knee as he started at the lights. His brow was mild and smooth and Donnie marveled at how young he seemed. "He's drugged."

Suddenly another panel, opposite their brother, rose. Thirty seconds later, a gearless Mikey was shoved inside. He spun, his lip drawn back and rushed at the hole even as it slammed back into place. Mikey sniffed at the blank surface, completely oblivious to his brother.

Who was staring at his back.

Ice flowed through the inventor's stomach.

Mikey worked his way left, his hands trailing over the wall. When he came to the window, he spread his fingers flat and exhaled a soft circle of moisture. Donnie strained forward, trying to examine his brother as the youngest tapped the glass, curiously.

"No..."

"Wha'?" Raph asked faintly.

"Look at his eyes."

Where should have been clear cerulean was a glinting shield of black.

Raph swore. "What is dat?"

"I have no idea."

Mikey's eyes trailed down a fixed on a spot near his elbow. His joyful face ignited with fury and he spun on his heel, tensing. Leo rose, snarling. His hands balled into fists. The youngest went forward, stretching to his toes to match his brother's height.

"Wh-what're dey -?"

Donatello's heart wrenched as he realized just what he was seeing. Mikey's blatant adoration of his oldest brother was gone. So was the subtle affection which always lined the leader's face. Leo's eyes sparked, dangerously, as he spread his shoulders and made a false charge, dropping Mike back a step. Leo eased away, the glass silencing the rough hiss he gave as he jerked his chin upward.

Don's tongue felt thick against the roof of his mouth. "They're challenging one another."

"For what?"

"I…I think it's territorial."

"WHAT?"

Leo bared his teeth and moved right, forcing Mikey to mirror the action. They crouched low, backs to the wall.

Raph's voice was low and tight again. "I didn' even know we were territorial."

A bitter smile touched the genius's mouth. "Who all is allowed near your room again?" Silence. They watched the circling continue, nauseous. "This is instinctual. They're mature males forced together in a small enclosure. It's only natural they'd have to establish a hierarchy between…"

"There ain't nothing _natural_ 'bout our brothas havin' a pisser over that POS room!" Raph roared. Then, he panted, "Leo'll kill 'im, won't he?"

Donnie flinched at the defeat in his brother's voice. He wished he could reach out to him, to even _look_ at him. To look at anything but the spectacle before him. "Not necessarily."

"Howya figure?"

He hesitated. They all knew he could not shut down the analytical side of his mind, but never before had he spoken his observations about any of _them_. It felt almost like a betrayal.

"Leo is most dangerous when he can detach, go cold. He sees fighting as an art and feels nothing when he loses himself in it. It becomes a task. A glorified kata he's already mastered. When he's not watching out for us, he's deadly. But Mikey treats a fight like a game he already knows he's winning. He runs on passion, making decisions on whatever feels right in the moment." He paused. "Passion is a lot closer to instinct than logic."

"So," came a deeper voice from behind, making them both jump. John Bishop emerged from Donnie's right, gliding to the window. "Who would you put your money on?"

"Bishop!" Raph hissed as horrified guilt tore Donatello's gut. He bit his lip, furiously. Of course Bishop had been with them this whole time! And he'd just given the man information on his brothers!

Stupid, stupid, stupid…

The agent's lenses flashed as he glanced back to them. "Good evening, gentlemen."

"Bishop, what is dis?" Raph snapped. "What did ya do to 'em?"

The man's eyes crinkled, merrily, as he returned his attention to the window, where the two mutants were still threatening. "My scientists have developed a serum I found quite intriguing. It lowers activity in the brain's frontal lobe, suppressing societal and habitual implications."

"Wanna try it in English, jerk?"

Donnie sighed, heavily. "Raph, the frontal lobe is where most of the personality is. Their reasoning, memories, inhibitions…"

"All temporarily repressed," Bishop grinned. "Isn't it astounding what science can do?"

A surge of heat stirred through Donnie. "This has nothing to do with - NO!"

His voice shattered as Leo leapt across the small space, a wild swing blazing over Mikey's head. He threw out his leg, catching the younger in the rump and sending him over the floor. Leo kicked off the wall and tackled the fallen warrior, grappling with him as they rolled. Mike twisted, violently, and sank his teeth into his leader's forearm. Leo's mouth went wide in a howl of pain and indignation as he ripped free.

Red dripped over white tiles. The leader stared, stunned, at the injury and slowly raised hate-filled eyes. Mikey's sneer was marred by his brother's blood. He charged now, his shoulder catching Leo in the gut and slamming him into the corner.

"Interesting," Bishop murmured.

Tears stung. It was far from interesting. It was grotesque and pitiful and Donnie prayed it wasn't being recorded. Leo would die of shame if he ever saw himself kneeing Mikey's side with a savage, half-cocked grin. Or discovering he'd thrown all his strength into a punch to his little brother's temple. "This is sick."

"We call it the 'Berserker,'" Bishop said, casually. Ignoring him. "Fitting, isn't it? The original test subjects tore each other apart. We've made adjustments as we could. But how much can you truly glean from rats?"

A gash lanced over Mikey's cheek.

A fierce uppercut pierced Leo's teeth into his tongue and blood flowed.

"I'm hoping your brothers can supply adequate results to enhance the serum. We just can't seem to find that pesky line between increased aggression and insanity." The agent tapped his chin, enthralled. "Just fascinating, isn't it? We all know Leonardo suffers from an alpha male complex. But to see it in Michelangelo as well…Interesting."

"Stop that!" Raph bellowed.

More droplets littered the tiles.

"Okay," Donnie breathed, angrily. "What do you want, Bishop? What do you want from us to stop this?"

Bishop hummed in his throat as Leo smacked headfirst into the glass and staggered back, dazed. Harder to see the difference in his dark eyes, but Donnie found the lack of intelligence in his leader's face to be just as chilling.

And heartbreaking. His shoulders heaved and his lips were drawn back, not to intimidate now, but to gulp air.

"Come on, Leo. Fight it!" Raph whispered. "Yer betta than this, bro! Just stop…"

Black fire erupted and the glass wavered as the eldest's fists slammed it in frustration. He spun back to an expectant and equally exhausted opponent. They tore at one another as they went down. Mikey's arm snaked out and he jammed his elbow back short and quick. Leo fell back, clutching an unnatural bulge from his shoulder. His heel caught Mike in the chin, snapping his neck back.

"Bishop, please!" Donnie wailed. "They're killing each other!" Leo backhanded the other with his good arm. "Look, you can have me instead! Whatever tests or samples you need, all right? Just stop this!"

The man stuck out his lower lip, as if considering. "No."

"No?"

"Honestly, Donatello, I'm not interested." He turned his back on the room, gliding before the turtle. "No offense, but I've lost enough equipment and expense on you. Besides, your DNA could still be corrupted from our last encounter. Any tests run would not be reliable. I don't need you…"

"Whaddabou' me?"

Raph's words, even whispered, felt like a slap. "No!"

"Shut-it, Braniac."

Bishop's eyes slid to his right and he eased just out of Donatello's sight. He jerked at his shackles, fighting his own growing scream of frustration. He wasn't accustomed to feeling helpless.

He heard the low taunt in Raph's voice and his brother's arrogant smile flickered behind Don's eyes. "C'mon, B. I'm healthy as a horse and free of your alien-goo. Tried smokin' once, didn' like it. Had a beer here and there, but how crucial is one turtle's liver to yer ol' serum?"

"Minimal."

"There you go. Just get them outta there an' I won't make a fuss 'bout anythin'. Deal?"

"Raph, you can't…" Donnie's voice broke.

"You were jes offerin', little bro."

"That's different!"

"Is it?" Bishop passed by with a smirk. He pressed his earpiece. "Send in Stone and Phelps. Cut the test, we have enough." He resumed his place at the window as Leo struggled to break free of a chokehold. Dark triumph flickered over the youngest's face. "Cut it now."

The lights went wild, flashing in and out. Donnie heard the faintest, muffled screech of an alarm.

Leo and Mikey fell away from each other, hands clamping over their heads. In the strobed light, he spotted a mean leaning through one of the panels to aim a tranquilizer gun. He ground his teeth as Mikey's bleeding frame went down. Leo crashed a second later and the siren died. Light flooded the room again as scientists rushed for the mutants.

A door crashed open behind them, followed by the heavy-soled clunk of boots. Two men wheeled Raph forward and around Donnie. And as he went by, the older turtle mouthed: _Do something!_

Donnie watched him go, bewildered. Do? What _could_ he do?

Bishop waited until the door slammed before reaching for his earpiece again. "Take the initial stats on Leonardo and then keep him sedated. I don't want him trying anything clever. And don't underestimate Michelangelo, he's the tricky one. Secure him and monitor any residual side-effects." He paused. "And double the guard in Lab 5, we're going to have trouble in there," he looked at Donatello with a slight smile, "promise or no promise."

He fell silent and his hands returned to his back. He continued to watch the swarming technicians. Donnie strained against at his restraints and attempted murder via glare. Both had failed results.

"Your eagerness to sacrifice yourself for the sake of your motley little family will never disappoint, will it? All four of you. Off goes your heroic sibling there, giving everything just to stop a silly little fight. Why? After all, he could be the next visitor to that room. I could break him in ways he can't fathom. Yet, there he goes. And I'll bet you'd be more than willing to take his place, knowing that." He snorted. "Rather self-destructive behavior, isn't it?"

"But it's our way," Donnie whispered. "Better myself than one of my brothers. It's a concept understood and just as natural as breathing." He lifted shadowed eyes. "You'd know what it's like if you really had something to fight for."

The man lifted a brow, smirking. "The rat let you watch after-school specials, didn't he?" He shook his head and turned to leave. "Don't worry, Donatello, you'll get your chance to play the hero. I've other projects which don't involve DNA at all. You certainly won't feel left out." The door clicked quietly behind them.

Donatello went a little crazy then, kicking and arching as best he could, but the straps wouldn't give. He swore, bitterly, and fell against the table, panting. He needed a plan. He needed Leo to give him a plan to execute. That was what Donnie did, figured out the _how_ to Leo's strategizing.

The scientists succeeded in hauling the leader onto a stretcher. Leo's arm flopped, placidly, over the edge and Donnie stared at it, hating his own helplessness.

_What do I do, Leo? You're in trouble. Mike and Raph are in trouble. And I'm stuck here! What can I do?_ He lowered his head, searching desperately for a stroke of genius…and found none.

_What do I do?_

_

* * *

_

* _peeks from behind Donnie's shoulder. _Seriously, what does he do? I got nothing! I can get them in these messes, but as to getting them out, there's the rub. Will probably remain a one-shot, sorry, I'm evil like this. But thanks for reading! Please let me know what you think!


End file.
